A circuit and method of analog data acquisition synchronization from an analog sensor in multiple channels associated with a USB hub. The reflective optical system has a first reflecting mirror for reflecting light emitted from the image forming device and initially applied thereto, and a plurality of reflecting mirrors for successively reflecting the light reflected by the first reflecting mirror. In this case, it is simultaneously necessary to ensure that only that software code which is not imperatively required for calculating a result for at least one of the unmarked subfunctions is masked out and is therefore not read in.